Wave signal rotary joint



Oct. 22, 1963 D. F. BOWMAN 3,

WAVE SIGNAL ROTARY JOINT Filed Sept. 16, 1960 5 Sheets-Sheet 1 Oct. 22,1963 D. F. BOWMAN 3,108,235

WAVE SIGNAL ROTARY JOINT Filed Sept. 16. 1960 5 Sheets-Sheet 2 M a I8 9/a /2 l/g l/4 I I l /7l a /9 2o 5' A I if a INVENTOR. 0 4 #/I A 501M144A frat Vac 1963 D. F. BOWMAN I 3,108,235-

Sept. 16, 1960 5 s eets-sheet s Oct; 22, 1963 D. F. BOWMAN 3,108,235

WAVE SIGNAL ROTARY JOINT Filed Sept. 16, 1960 5 Sheets-Sheet 4 BY057K010; flee-1 6595 g SOFFFA/ Oct. 22, 1963 D. F. BOWMAN 3,1

WAVE SIGNAL ROTARY JOINT Filed. Sept. 1e, 1960 5 Sheets-Sheet 5 UnitedStates Patent 3,103,235 WAVE SHGNAL ROTARY .llllNT F. Bowman, Wayne, Pa,assigns: to i-T-E Qireuit Breaker (Iompany, Philadelphia, Pa, acorporation of Pennsylvania Filed Sept. 16, 1966 Ser. No. 56,496 21Claims. (Cl. 333-1) This invention relates to novel wave signal rotaryjoints or couplers that are capable of efficient transmission ofmicrowave signals between an output port that is continuously rotatablewith respect to its input port.

in accordance with the present invention, novel rotary joints areprovided that are capable of handling higher peak and average signalpower than heretofore; operable over broader bands of signals; that arereadily incorporated about sizable axial structures such as the radarmasts or torque tubes; and that are particularly advantageous in theircapability of incorporating a number of signal channels simultaneouslywithout interference.

The wave signal rotary joints hereof are an aroundthe-mast type, thatovercome restrictions in existing rotary joint constructions, andprovide capability of meeting difficult combinations of performancerequirements including broad-band operation, hi h power utility, lowSWR, low wow, and handling of threeor more well isolated signal channelsacross the rotary joint. My invention provides rotary joints which arein microwave systems involving relative motions, particularly those withmovable antennas. This includes antennas for radar, communications,radiotelescopy, etc., and in particular on antenna with a number ofsignal channels. However, the advantages of my novel rotary jointindicate its usefulness even for single channel applications.

The invention rotary joint principles are applicable, with no limitationintended, over the signal range of 300 megacycles per second to 100kilomegacycles per second. The invention joints are useful wherever waveguides are employed and a rotary joint indicated for the system. Bandwidth ratios of 2:1 are realizable, with losses of less than 1 db, andeven as low as 0.1 db. The practical power handling capability of theinvention rotary joints is of the order of to 50% of the rated power ofthe wave guide appropriate for the selected frequency of design. TheSWR, and impedance discontinuity presout no problem herein, beingovercome comparably or better than in prior rotary couplers and joints.

Broadly, the rotary joint of the present invention comprises threedifferentially rotatable sections mountable about a central axis alongwhich may lie a rotary member or mast. in a vertical version, the bottomand upper sections are the launching members, each arranged withseparate signal launching means for each channel. The central section isgenerally drum-like with a hollow cylindrical type of envelope throughwhich the mast is oriented. The central drum is constructed, in themanner to be hereinafter described, to conduct or direct signal energyfrom a series of points on one end thereof, across the drum to acorrespondin series of points on the other drum end, whereby relativerotation of the drum and the contiguous launching sections effects thedesired multichannel transmission between the launching members.

Differential rotation is established. between the rotary joint sections.By suitable gearing the relative phasing of multi-channel feed-throughand their synchronization with corresponding launching members, isdirectly accomiished, as will be set forth hereinafter. Where onelaunching section, as the bottom one, is held stationary, the centralsection is rotated at half the angular rate of the top section. it isfeasible to array two or more of ddbdlid I Patented Oct. 22, 1953 2 suchthree-section rotary assemblies coaxially, as by axial staggering or bynesting one within the other, to provide more signal channels inaddition. The present invention is thus useful as a rnulti-channel radiofrequency including microwave rotary joint.

It is accordingly a primary object of the present invention to provide anovel wave signal rotary joint with multichannel capability.

Another object of the, present invention is to provide a novel wavesignal rotary joint or coupler composed of three relatively rotatablealigned sections through which the signals are projected andsynchronized as separated channels.

A further object of the present invention is to provide a novel wavesignal rotary joint having a central hollow cylindrical rotatable drumtype section that conducts or directs the signals between separated endlaunching sections.

Still another object ofthe present invention is to provide a novel wavesignal rotary joint composed of three aligned hollow sections ofcylindrical envelope that are respectively differentially rotated forsynchronized multichannel signal transmission therethrough.

Still a further object of the present invention is to provide a novelwave signal rotary joint with relatively high power handling capability,relatively broad-band operation, and relatively low SWR, or low wow.

These and further objects of the invention will become more apparentfrom the following description of exemplary embodiments thereof;illustrated in the drawings, in which:

FIGURE 1 is a schematic showing of a radar system incorporating amulti-channel Wave signal rotary joint in accordance with the invention.

FIGURE 2 is a diagrammatic perspective representation of the wave signalrotary joint.

FIGURE 3 is a simplified illustration of the rotary joint constructionand a form for its rotary drive.

FIGURES 4 to 7 are system diagrams of organ-pipe arrays used inillustrating principles of my novel wave signal rotary coupler.

FIGURE 8 is an assembly view of an exemplary rotary coupler.

FIGURE 9 is a bottom view of the rotary joint as seen in FIGURE Horns A,B and C are shown in phantom and the drum section is omitted.

FIGURE 10 is a bottom view taken in the direction of arrows lilll of onesection of the organ pipe drum array of the coupler of FIGURE 8.

=FIGURE 11 is a diagrammatic representation of the organ pipe array, andof its paths.

FIGURE 1 is a schematic illustration of a radar system utilizing threewave signal channels. The radar antenna 15 extends from frame 16, and isrotated by the central shaft or mast 17 through drive motor 18 andgearing l9, The radar antenna unit 15 is shown connected with threesignal wave guides or cables 21, 22, 2.3; which of course may be two orfour guides, or more, depending on the type of the system. Themulti-channei cables 21, 22, 23 are afiixed to the rotatablesuperstructure being rotated with the antenna 15 on mast 17. The cables2. 22, 23 terminate in the upper launcher section 26 of the rotary joint25'. The cables may be passed through the inside of gear 19 asillustrated so that they will not be cut off by the motor mounting.

The rotary joint 25 is shown in block form, as mounted concentricallyabout the mast i7, 17'; being in generally cylindrical form. Thephysical rotary joint (25) of this invention may assume many forms andembodiments; as will be described hereinafter. However, such variousforms and combinations, for specific rotary joint purposes oradvantages, basically correspond in arrangement and coaction to thediagrammatic representation 25 in FTGURE 1. The wave signal rotary joint(2%) in accordance with the present invention is composed essentially oftwo end launcher sections 26 and 28, each operationally related with anouter region 39, 31 of central drum section 27; the drum 27 and one endlauncher section (26) being rotated at a differential rate, with theother end launcher section (28) being preferably (though notnecessarily) stationary.

Towards this end, the lower end launcher section 28 is secured at 32 tomast extension 2.7 that is stationary; and upper launcher section 26, at33 to the rotatable mast 37. Section 26 thus is rotated by motor 13, andwith the antenna 15 and multi-cables 21, 22, 23. The central drumsection 27 is geared to upper launching section through schematicallyillustrated differential gearing 35, anchored as at 34- to the interiorof drum 27. The interior of the rotary joint sections 26, 27 and 23 arehollow, and they are readily designed to fit around a drive shaft ormast (17, 17). Their electrical action per this invention is preferablyarranged along the outer cylindrical region of the respective sections 26, 27, 28.

Relative rotation of the rotary joint sections 25, 27 28 is requisite incarrying out the principles of the present invention as will be setforth. Such rotations may be effected by internal gearing as indicatedin FTGURES and 3, or by corresponding gearing or drives external of therotary joint 25. FIGURE 3 illustrates in diagrammatic section aninternal differential gearing array (35) and the coaxial arrangement ofthe rotatable active cylindrical sections 26, 2'7, 23 of tl e rotaryjoint 25. Upper launching section 26 is secured to a central shaft 37, arotatable one as 17; across a web 36 secured with section 26. The lowerlauncher section 28 is correspondingly secured to the stationary shaftextension 37 through web 38.

The central drum section 27 is coupled to shafts 37, 37 through webs 39,4t and ball-bearings 4-1, 42. The pinion 43 of differential gearing 35is mounted on a post extending from drum 27 interior, and coacts withbevelled gears 45, 46 to effect the differential drive. The exemplaryrequirement, as will be explained hereinafter, is for the central signaltranslation drum 27 to be rotated at exactly half the angular rate ofthe upper launcher section 26 where the lower one 23 is held stationary.Suitable prcportioning of the gear drive 35 readily effects such driverelation, or any corresponding one were all three sections made movable.Other drive means, internal or external of rotary joint 25 to eifectsuch desired operation may be employed instead, as will be understood bythose skilled in the art.

With the lower end launching section 28 held stationary, the pluralityof wave guides or cables connected thereto are readily integrated asshown in FIGURE 1 at d7, and 49. The individual wave signals areintroduced to or conducted from corresponding cables 47, 4-8, 49. Thetransmitting and/or receiving equipment or instruments are connectedwith the cables 4'7, 48, 49, at a remote location. The wave signalchannels are simultaneously connected through the guides 47, 43, 49 withthe lower stationary launching section 255. The multi-channel signalsare then related to the adjacent drum (translator) rotatable section 27,on an end-to-end or equivalent peripheral signal coupling basis.

A significant feature of the invention system is to translate theindividual channel signals on a rotational basis, with differentialspeeds of the joint (25') sections (26, 27, 28) effectingsynchronization and channel isolation. Several practical forms for thecentral drum translator section (27) are illustrated and describedhereinafter. The basic advantages hereof accrue from the genericarrangement of either a single or multi-channel array of end launcherswith an intermediate differentially motivated translator section, toeffect an efficient, clean transition across a mechanical rotaryconfiguration.

A general description of the wave signal rotary joint is now presented,in connection with FIGURE 2, illustrating the rotary joint 59 indiagrammatic perspective view. The top or upper section 51 has a seriesof launching devices A, B, one for each channel desired. The devices A,B are shown as horns, but may be of other types, as will be shown. Therespective launching devices A, B are each arranged to couple from a topport a, b to a corresponding portion of the top circumference 52 (oradjacent thereto) of the central drum section 53. As explained inconnection with top section 26 of FIGURE 1, wave guide or cableconnections extend from the ports a, b to the utilization structure (15)rotated with the top launching section 51.

The central section 53 corresponds to the drum or hollow cylinder 27 ofthe rotary joint 25 (FIGURE 1). The drum or wave translation section 53is differentially rotated with respect to top launching section 51 (andthe bottom one 55), as will now be understood. The central section 53conducts or directs the individual signal channels from one set oflocations on its upper end circumference region 52 to its other endcircumference region 54. Significantly, however, the location points asl, 2, 3 11 at the region 54- are not correspondingly longitudinallyopposite the points 1, 2, 3 11 of region 52. The order of the numberedpoints of region 54 is in the opposite rotational direction to that ofregion 52, and in general physically displaced angularly. Such centralwave translation array (53) coupled with the differential angularrotation of the sections 51, 53, 55, combine to provide the advantageousrotary joints of the invention, to be more fully described.

The bottom launching section 55 has launching devices A, B correspondingto those of section 51. Launchers A, B are located along thecircumferential region 54 of central section 53, at similarly numberedlocation points to their companion launchers A, B. In this way, theisolated channels AA, B-B', etc. are conducted across the rotary joint(5%), through the central rotating translation section (53). Chokes orcontacts, and/ or other elements (not shown), may be provided to effectefficient coupling from the launching devices to the correspondingactive circumferential regions (52, 54) of the drum (53 as will beapparent to those skilled in the art. The bottom ports a, b of the hornsA, B, couple to corresponding wave guides to the electrical operatingequipment.

In essence, the wave signal rotary joint of the present inventionprovides a unique translation of wave signals (single or pluralchannels) between two launching sections that are movable (rotatable)with respect to each other, whereby uniform conduction or direction(channel transmission) is elfected of the wave signals betweencorresponding ports (for channels) of the launching sections. Asmentioned, both the launching sections or the central drum (wavetranslation) section may take various exemplary forms. The drumembodiment of FIGURES 7 through 11 utilizes an array of closely spacedwave guide tubes or organ-pipes. Reference is now made to FIG- URES 4, 5and 6 for a preliminary explanation of the principles and operation ofthe more complex drum 39 system.

FIGURE 4 may be considered as a developed view of a series 69 ofcontiguous wave guide tubes or organ-pipes 61, 61. The preferred mode iswith the tubes 61, 61 arrayed in the E-plane. The launching sections 62,63 contain feed horns A, B and A, B respectively; each coupling to aplurality of tubes 61 (three in this example). The feed horns arepreferably of the E-plane sectoral form, firing into the open ends ofthe organ-pipe tubes 61. As a rotary joint the developed tubes 61, 61would be rolled into a cylindrical or drum form, as the central section.The wave signal channels exist as AA and 13-3 between the launchingsections 62, 63.

With the launching sections 62, 63 held stationary, or moved insynchronism, the illustrated in-phase, horn-t0- horn position of thechannels are held intact, and their transmission across the organ pipesis unaffected. Similarly if the central drum 60 is rotated or movedacross the horn paths, the "channel transmission is still unaffected. Asimilar condition prevails where the organ pipes 66, 66 are inclined, asin the drum 65 of FIGURE However, to maintain channel integrity, it isnecessary to position or phase the respective channel horns AA' (etc.)at corresponding pipe (66) endings. Neither system 6t) or 65 willprovide channel integrity with relative movement or rotation between theupper and lower horns or launching sections 62, 63, as requisi e in arotary joint.

A significant feature of the present invention is to provide a uniquerotating drum configuration that translates the wave si nals between twospaced launcher. sections that are in relative rotation; and maintainschannel integrity between the launcher sections. FIGURES 6 and 7 arediagrammatic representations of methods for accomplishing such wavesignal translation. The central drum 70 of FIGURE 6 contains twoidentical crossed organ-pipe sections 71, 72 each subtending 180 of thecylindrical envelope of drum 7t). The launching sections 73, 74- eachcontain three-channel horn sets A-A, B- B and C-C, set to thesequentially into adjacent open ends 1, 2, 3 20 of the organ-pipes 75,.75 of each pipe section 71, 72. The pipes 75, 75 are drawn as singlelines for clarity of illustration.

The organ-pipes 75 are sequenced in drum 7 t) with their end groupings,at opposite drum ends, being inverted or in reversed angular orientationend-to-end for each section 71, '72, as illustrated. The twenty pipeends at each drum end cover the 360 circumference, in this example; withmore or less pipes '75 being usable in a particular construction. Onlyone groupings of pipes 75 may be used over the 360 of a drum, but thetwo sets 71, 72 are more advantageous in that the longest paths, as 1-1and. 10 of drum 70, are substantially shorter than those for acorresponding single array. The double pipe grouping of drum saves aboutone-half overall over a single crossed array for the same drum size.

Relative rotation between the launcher sections 73, 74 of FIGURE 6, aswith section 73 moving in one direction a, and the other section 74 indirection a opposite to a and of equal rate with respect to central drum70, results in unchanged channel transmisison, between channel pathsA-A, 13-3, and CC. The reversal of organpipes (75) end-to-end in drum 7%results in the same relative OW. or C.C.W. viewing by the respectivelaunching sections 73, 7d.

The reverse angular sequencing of horns A, B, C as illustrated, and theequal and opposite (angular) displacement rate of these horns A, B, Cwith respect to the drum 7% as noted, results in identical relativetransmission and channel integrity for the two rotating launchingsections 73, 74. Where it is desired to hold a launching section aslower one (74) stationary, then it is necessary only to rotate thecentral drum (7t?) at exactly one-half of the angular rate of rotationof the top launching section (73) to maintain the signal circuitstability and continuity. Differential gearing 35 as per FIGURE 3 orequivalent means may be used in practice for this purpose.

While the rotary joint system of FIGURE 6 uses three wave signalchannels, additional pairs of launchers may be added for each newchannel. An upper limit on the number of channels is determined by thenumber of wave guide tubes or organ-pipes required per channel. Inpractice, a suflicient number of pipes should be engaged by eachlauncher element to provide acceptable commutation ripple and to provideadequate power handling capability. In addition, the channels arepreferably separated by a number of idle pipes to provide optimum signalisolation among the channels.

The wave path transportation by the organ-pipe array 70 of FIGURE 6, orits counterpart with one 360 pipe array, are useful embodiments. Theyprovide excellent multi channel isolation, and are relatively simple andinexpensive to construct even for large power designs. Each organ-pipepath'is of equal electrical length. This affords uniform electricaltransmission characteristics over broad hands of frequency of operation,and for a number of channels. FIGURE 7 is a diagram of a drum array oforgan-pipes 8%. An exemplary orgampipe drum embodiment is illustratedand described in connection with FIG- URES 8 through 11.

The drum till of FIGURE 7 comprises two identical organpipe arrays 81,82, each subtending 180 of the circumferential extent of the drum. Eachpipe array 81, @2 is composed of ten signal wave guide tubes with walls1, 2, 10 and 11 through respectively. These tubes or pipes are allalike, are uniformly spaced, and terminate at opposite axial ends of thedrum 84 It is to be understood that FIGURE 7 is a developed diagram ofthe three-dimensional array making up the cylindrical hoop form of thedrum till. The ten pipe array 81 envelopes the 0 to 189 positionsmarked; and array 82, the 180 to 366 positions. While ten organ-pipesare illustrated for each array 81, 82, it is evident that a fewer or agreater number per array may be used in a given design.

A significant characteristic of the arrangement of the organ-pipes withwalls 1, 2 20 is their method of routing in each array $1, 82. Thesewave guides are nested together with compound bends at b, c j asindicated in the drawings; which bends occur along the starting region 0or 180 of the arrays. Typical routes of the 81 array are 2-b-2, 3-c-3,etc. An important advantage of such array is that each bend b, c i, canbe made to be similar; and the total length of each pipe with walls 1, 211, made substantially identical both mechanically and electrically.This insures uniform electrical operation across the rotary coupler forthe eliective signal channels. Other advantages accrue as will be setforth in connection with the description of FIGURES 8-11 hereinafter.

The pipe arrays 31, d2 are thus each in a 180 sector of a cylindricaldrum or seini-toroid; and in effect mate end-to-end across their 0180-360O axial planes. Each array (81, S2) is compact, radially, being nomore than about two wave guides thick. In fact, additional sets ofarrays may practicably be nested concentrically with the set 81, 32, andthereby materially increase the isolated channel capacity of a systemwith little increase in radial extent.

Three sets of launchers at each end launching section 83, 84 areillustrated, although fewer or more channels may be used inanyparticular embodiment. The sequence A, B, C of launcher set 83 isreversed from the other set 84, B, A", C. This factor, coupled with therelative differential rotation of the launchers 33, 84 and drum till, inthe manner hereinabove set forth, results in the multi-channelsynchronization and isolation required. Basically, the reversed phasingof the pipe ends at 11, 10", 9 1', adjacent launching section 34, andits reversed launcher array B', A, C, affords the same relative seeingthe drum aspect as the companion launchers in section 8 3 at theopposite drum end.

With drum 3% stationary, the respective launching sections 83, 84 wouldhave to rotate at equal angular rates but in opposite directions (VJ/ tomaintain channel synchronization of the associated plural wave signals.Correspondingly, as most often in practice, with one launching section(84) held stationary, the drum is rotated at one-half the angular rateof the other launching section (33), and in the same directiontherewith. Differential gearing for this purpose is hereinbeforedescribed, or equivalent means are used.

FIGURE 8 is a side elevational view of an exemplary rotary coupler Millbased on the reentrant nested organpipe array, showing one bank or array101 of ten wave guide tubes ll, 2-2 10-10, formed and shaped into athree dimensional two pipe layer drum sector about center c-c. Othersector arrays as the 101 section are used in the rotary coupler 100system as will be described. Reference is made to FIGURE 7 and theattendant description for the principles of arrangement and operation ofthe pipe array 101. The compound bends of the array pipes are arrangedat a, b j for the successive tubes 1-1, 2-2 etc. Furthermore, themechanical lengths and electrical properties of all these tubes is madethe same for the reasons heretofore stated.

A plurality of drum coupling guides 111, 112 120 extend from theopenings 1, 2 of the organ pipes; and a similar set 111, 112 120 fromthe opposite side 1, 2 10, as seen in FIGURE 8. Not all the couplingguides are shown, for the sake of clarity of presentation. The drumcoupling elements pairs 111, 111; 112, 112, etc. effect practical wavesignal guides between the corresponding launcher sections 125, 130 andthe respective successive organ-pipes of the array 101.

There is arranged a small practical clearance at between the outercoupling ends of the elements 111, 112 2.0 and the launching section125; and one a" on the corresponding location for section 130. The drumcoupling elements 111, 112 etc., and 111, 112 etc. are narrowed at theirorgan pipe ends. The clearances d and d permit the relative rotationrequired, as previously set forth, between the respective drum andlaunching sections 100, 125, 130. The regions across d and d are thecommutation planes between the organ pipes l, 2 etc. and thecorresponding launching units.

The launching sections 125 and 130 are similar, having three independentchannels with corresponding horns A, B, C, and B, C, A. Each of thesehorns is proportioned subtend three coupling elements 111, 112, etc. or111, 112 etc., with a corresponding number of pipe port intervalsbetween them. The two half-drum arrays as 101 provide 20 ports, overwhich the three channels coact on an end region 360 circumferentialbasis, as will now be understood by those skilled in the art. The threechannels AA, B-B, and C-C are electrically isolated, and theirtransmission across the rotary coupler negligibly impeded and negligiblydistorted. The Wave signals respectively couple to the ports of thelauncher horns. High power, efficient multi-channel operation iseffective therewith. The system is rotatable along center-line C-C; thecentral mast or shaft being arranged inside the sections, coaxially withC-C.

FIGURE 9 represents in layout the relative positions of the two sets oflaunchers A, B, C, on the inside radius, and A, B and C on the outerradius. The angular relationship between two sets corresponds to that ofFIGURE 8 as viewed from the bottom.

FIGURE 9 is an end view of the rotary coupler of FIG- URE 8, as seen atthe launcher section 125 side, with the respective ports 126, 127, 12-8of horns A, B, C visible. The 120 circumferential spacing of the hornsA, B, C is evident in FIGURE 9. Their coupling with the drum elements111, 112, etc., is not drawn in, for clarity, but is clear from theview, FIGURE 8. A companion set (130) A, B, C is shown (in dotted lines)thereupon arranged on the opposite side of the central drum (100) aswill be now understood. Also, a separate drum array of organ pipes,concentric about the dual 180 sector array (101), is understood toco-act with the said nested launching sections 125 and 130. Six-channelwaves signal rotary coupling is thereby effected in a compact fashion.

An end view of a typical organ-pipe 180 cluster on 180 drum sector, perse, is illustrated in FIGURE 10. The array 101 corresponds to a viewtaken along 1010 of assembly FIGURE 8. The initial guide tube 1-l' hasits start port (1) opposite, radially, the end port (10) of tube 10-l0.Correspondingly port 2 of tube 2-2 is radially opposite port 9 of tube99, etc., until somewhat less than 180 away the tenth tube 10-10 startport 10 is radially opposite the end port 1 of tube 1l. By such uniquereentrant nesting, a two layer gs 0 guide pipe array is provided,wherein its sector extent is within 180 of arc in a plane perpendicularto the rotation axis cc (i.e., in the plane of FIGURE 10.

T he curved end of array 101 characterizes the region of the compoundbends a, b, c j (see FIGURE 8) for the tubes l1, 2'2, etc., with thebend j in view for tube 10-10. The organ pipe array 101 of FIGURES 8 and10 is understood to be symmetrically nested with one exactly like it tocomplete the 360 pattern for the drum. This is readily done by a foldover.

The path diagram for each of the ten organ-pipe arrays, corresponding to1.01, is shown in FIGURE ll. This diagram is for a 180 are of rotationas is understood for the 180 drum sector type (101). As the 180 sectorsare nested for a 360 cycle, a continuous 20-pipe 360 array is presentedto the adjacent launcher sections. Corresponding pipe ports 1,2 10, and1, 2 10, as well as the compound bonds (1, b, c j of the diagram referto the units (101) as illustrated in FTGURES 8 and 10. it is noted thatthe electrical character and mechanical length of each path isidentical. This results in minimal distortion and maximum efiiciency.

The launching sections of the invention rotary couplers may assume otherpractical forms than the simple horn pairs, channel-to-channel hereinillustrated. For example,

one may employ an integral number of horn pairs per channel. The latterwould increase power capability by combining outside of the rotaryjoint. Also, idle horns may be used for control of channel isolation.The horn launchers may be arranged to fire longitudinally, asillustrated, or the system oriented for tilted firing (angular andoblique); or even radial firing, including use as phase front Corrector.

Alternatively, more perfectly focussed line sources may be used aslauncher elements, as parabolic pill-boxes (single or multiple layer);lensed horns; array of horns, probes, etc. The launching sections arecircularly arrayed for coaction with the corresponding end regions ofthe drum translator, as set forth. Another particularly advantageouslauncher is a traveling-wave slot array type, in cylindrical form, asshown in the copending patent application Serial No. 60,025, filedOctober 3, 1960, entitled Concentric Rotary Coupler for Wave Signals, inthe name of David F. Bowman, and assigned to the assignee of the instantinvention.

he central drum wave signal transmission (transposer translator)sections have herein been illustrated and described in connection withseparate-path nested wave guides or organ-pipes. These pipes, of course,may be used in an E-plane or H-plane commutating mode, or in combinationas shew plane commutation. Further, TEM lines may be used for the nestedseparate-path drum, in coaxial or strip-line form, or in combinationwith wave guides, as will now be evident to those skilled in the art.

An important variant to such separate-path drum (organpipe) system isthe use of a common path or parallel plate arrangement. In such latterdrum, two concentric conducting surfaces or sleeves serve as boundariesof tho common-path for the multi-channel wave signals, with suitablereflectors or refractors effecting the signal transposition. Referenceis made to the referred to copending patent application for specificillustrations thereof.

Although the present invention has been set forth with exemplaryembodiments, it is to be understood that variations and modifications asto the forms, arrangements and applications it may assume in practicewill present themselves to those skilled in the art, and that it is notintended to be limited except as set forth in the following claims.

I claim:

1. A wave signal rotary coupler comprising a first and a secondlaunching section, a central transmission section for conducting wavesignals of a plurality of separated channels in transposed space phaserelation cnd-to-end thereof, said launcher sections individuallycoupling with said transmission section, and mechanism for driving saidarouses sections to eifect plural channel wave signal transmissionbetween said first and second launchin sections with said sections inrelative motion. I

2. A wave signal rotary coupler comprising a first and a secondlaunching section, a central transmissionseetion for conducting wavesignals therethrough in transposed space phase relation end-to-endthereof, said launcher sections individually coupling with saidtransmission section,

and mechanism for differentially driving said sections. to

effect wave signal transmission between said first and second launchingsections with said sections in relative motion.

3. A wave signal rotary coupler comprising a first and a secondlaunching section each arranged in a generally 360 peripheral array, acentral drum transmission section for conducting wave signalsthercthrough in the direction of its axis and in transposed space phaserelation end-toend thereof, said transmission section including aplurality of adjacently arrayed waveguide pipes, said first and secondlauncher sections individually coupling with said transmission sectionacross its pipe array, and mechanism for difierentially rotating saidsections completely about said axis to effect wave signal transmissionbetween said first and second launching sections with said sections inrelative angular motion.

4. A wave signal rotary coupler comprising a first launching sectionarranged in a generally toroidal array containing a plurality ofindividual launcher units, a central cylindrical transmission sectionfor conducting wave signals therethrough across its peripheral region inthe direction of its axis of rotation and in transposed space phaserelation end-to-end thereof, said transmission section including aplurality of adjacently arrayed organpipes, and a second launchingsection corresponding to said first launching section with its launcherunits arrayed in transposed space phase relative to those of said firstlaunching section, said first and second launcher sections individuallycoupling with said transmissionsection along a respective peripheral endregion thereof.

5. A wave signal rotary coupler comprising a first launching sectionarranged in a generally cylindrical array containing a plurality ofindividual launcher units spaced apart by substantially the same anglealong the array peripheral region, a central cylindrical drumtransmission section for conducting wave signals of a plurality ofseparated channels therethrough across its peripheral region in thedirection of its axis of rotation and in transposed space phase relationend-to-end thereof, a plurality of adjacently arrayed wave guide pipesof substantially the same wave signal conduction characteristics, saidpipes being arranged with their respective end ports exposed in adjacentpositions along the corresponding end region of said transmissionsection, a second launching section corresponding to said firstlaunching section, said launcher sections individually coupling withsaid transmission section along a respective peripheral end regionthereof, and

' mechanism for differentially rotating said sections to efiect pluralchannel synchronized Wave signal transmission between said first andsecond launching sections with said sections in relative angular motion.

6. A wave signal rotary coupler comprising a first launching sectionarranged in a generally toroidal m'ray containing a plurality ofindividual horn units spaced apart by substantially the same angle alongthe array peripheral region, a central cylindrical drum transmissionsection for conducting wave signals of a plurality of separated channelstherethrough across its peripheral region in the direction of its axisof rotation and in transposed space relation end-to-end thereof, saidtransmission section including a plurality of adjacently arrayedorgan-pipes of substantially the same electrical and mechanical lengthand wave signal conduction characteristics, said pipes being arrangedwith their respective end ports exposed in adjacent positions along thecorresponding end region of said transmission section in respectivecommutation planes ltd perpendicular to said rotation axis, a secondlaunching section corresponding to said first launching section with itshorn units arrayed in transposed space phase relative to those of saidfirst launching section, said first and-second launcher sectionsindividually coupling with said transmission section along saidcommutation planes and a series of coupling elements between said pipeend ports and the respective launching sections.

7. A wave signal rotary coupler comprising a first launching sectionarranged in a generally 360 peripheral array containing a plurality ofindividual launcher units spaced apart by substantially the same anglealong the array peripheral region, a cylindrical drum transmissionsection for conducting wave signals of a plurality of separated channelstherethrough across its peripheral region in the direction of its axisof rotation and in transposed space phase relation end-to-end thereof,said transmission section including a plurality of adjacently arrayedwave guide pipes of substantially the same wave signal conductioncharacteristics, said pipes being arranged with their respective endports exposed in adjacent positions along the corresponding end regionof said transmission section, a second launching section correspondingto said first launching section with its launcher units arrayed intransposed space phase relative to those of said first launchingsection, said first and second launcher sections being coupled to saidtransmission section along said end regions, and mechanism fordifferentially rotating said sections to effect isolated plural channelsynchronized wave signal transmission between said first and secondlaunching sections.

8. A wave signal rotary coupler as claimed in claim 5 in which saidtransmission section is angularly motivated at one-half the rate and inthe same direction as said first launching section.

9. A wave signal rotary coupler comprising a first launching sectionarranged in a generally 360 peripheral array containing a plurality ofindividual launcher units spaced apart by substantially the same anglealong the array peripheral region, a cylindrical drum transmissionsection for conducting wave signals of a plurality of separated channelstherethrough across its peripheral region in the direction of its axisof rotation and in transposed space phase relation end-to-end thereof,said transmission section including a plurality of adjacently arrayedwave guide pipes of substantially the same wave signal conductioncharacteristics, said pipes being arranged with their respective endports exposed in adjacent positions along the corresponding end regionof said transmission section, a second launching section correspondingto said first launching section with its launcher units arrayed intransposed space phase relative to those of said first launchingsection, said first and second launcher sections being coupled to saidtransmission section along said end regions, and mechanism fordilferentially rotating said sections to effect isolated plural channelsynchronized Wave signal transmission between said first and secondlaunching sections in which said transmission section is angularlymotivated at one-half the rate and in the same direction as said firstlaunching section with said second launching section being heldstationary.

10. A wave signal rotary coupler as claimed in claim 5, furtherincluding a second transmission section mounted concentrically with thefirst said transmission section, and third and fourth launching sectionsrespectively mounted with the first and second ones for electricalcoaction with said second transmission section in plurality concentricrotary coupling.

ll. A wave signal rotary coupler as claimed in claim 6, furtherincluding a second transmission section mounted concentrically with thefirst said transmission section, and third and fourth launching sectionsrespectively mounted with the first and second ones for electricalcoaction with said second transmission section in plural concentricrotary coupling.

12. A wave signal rotary coupler comprising a first and a secondlaunching section each arranged in a generally 360 peripheral array, acentral drum transmission section for conducting wave signalstherethrough in the direction of its axis and in transposed space phaserelation end-toend thereof, said transmission section including aplurality of adjacently arrayed wave guide pipes, said first and secondlauncher sections individually coupling with said transmission sectionacross its pipe array, and mechanism for differently rotating saidsections completely about said axis to effect wave signal transmissionbetween said first and second launching sections with said sections inrelative angular motion in which said pipes are arranged in twocontiguous groups each about 186 in peripheral extent.

13. A wave signal rotary coupler as claimed in claim 5, in which saidpipes are arranged in two contiguous groups each about 180 in peripheralextent, each said pipe group sing in a double tier with compound bendsfor maintaining their uniform electrical transmission characteristic.

14. A wave signal rotary coupler as claimed in claim 7, in which saidpipes are arranged in two contiguous groups each about 180 in peripheralextent, each said pipe group being in a double tier with compound bendsfor maintaining their uniform electrical transmission characteristic.

15. A drum transmission section for conducting wave signals in a rotarycoupler comprising a plurality of adjacently arrayed wave guide pipes intransposed space phase relationship end-to-end thereof and ofsubstantially the same fixed wave signal conduction characteristics.

16. A drum transmission section for conducting wave signals in a rotarycoupler comprising a plurality of adjacently arrayed wave guide pipes intransposed space phase relationship end-to-end thereof and ofsubstantially the same fixed wave signal conduction characteristics,said pipes being arranged with their respective end ports exposed inadjacent positions along corresponding end region of said transmissionsection.

17. A wave signal rotary coupler as claimed in claim 15, in which saidpipes are arranged in two contiguous semi-cylindrical groups each about180 in peripheral extent.

18. A wave signal rotary coupler comprising a rotatable cylindricaltransmission section providing multiple wave signal paths ofsubstantially equal transmission characteristics each from one of manystations spaced about a first annular coupling zone to the correspondingone of an equal number of correlative stations spaced in a transposed orreversed sequence about a second annular coupling zone, a firstlaunching section containing one or a plurality of individual launcherunits each providing an isolated wave signal path between an externalport and a segment of the first annular coupling zone, a secondlaunching section containing a like number of individual launching unitseach providing an isolated wave signal path between an external port anda segment of the s cond annular coupling zone corresponding in stationor stations to a segment of the first annular coupling zone engaged by alauncher unit of the first launcher section, and mechanism formaintaining such relationship while permitting relative rotation betweenfirst and second launching sections completely about the axis common tothe transmission section and the annular coupling areas.

19. A drum transmission section for conducting wave signals in a rotarycoupler comprising a plurality of adjaccntly arrayed wave guide pipes intransposed space phase relationsaip end-to-end thereof and ofsubstantially the same fixed WEIVC signal conduction characteristics,said pipes being arranged with their respective end ports exposed inadjacent positions along corresponding end region of said transmissionsection, in which said pipes are arranged in two contiguoussemi-cylindrical groups each about 180 in peripheral extent, each saidpipe group being in a double tier with compound bends for maintainingtheir uniform electrical transmission characteristic.

20. A wave signal rotary coupler comprising a first and a secondlaunching section, a central transmission section providing a pluralityof wave signal paths each from one of many stations about its upper endto a corresponding one of an equal number of correlative stations at itslower end, said upper end stations being arrayed in a first direction,and said lower end stations being arrayed in a second direction, saidlauncher sections individually coupling with said transmission section,and mechanism for driving said sections to effect plural channel wavetransmission between said first and second launching sections with saidsections in relative motion.

21. A wave signal rotary coupler comprising a first and a secondlaunching section, a unitary central cylindrical transmission sectionproviding a plurality of wave signal paths each from one of manystations about its upper end to a corresponding one of an equal numer ofcorrelative stations at its lower end, each of said paths being in aconstant fixed direction relative to the axis of rotation of saidcentral cylindrical section, each of said directions being other thanparallel to said axis, said launcher sections individually coupling withsaid transmission section, and mechanism for driving said sections toeffect plural channel wave transmission between said first and secondlaunching sections with said sections in relative motion.

References Cited in the file of this patent UNITED STATES PATENTS2,947,955 Bellamy Aug. 2, 1960

2. A WAVE SIGNAL ROTARY COUPLER COMPRISING A FIRST AND A SECONDLAUNCHING SECTION, A CENTRAL TRANSMISSION SECTION FOR CONDUCTING WAVESIGNALS THERETHROUGH IN TRANSPOSED SPACE PHASE RELATION END-TO-ENDTHEREOF, SAID LAUNCHER SECTIONS INDIVIDUALLY COUPLING WITH SAIDTRANSMISSION SECTION, AND MECHANISM FOR DIFFERENTIALLY DRIVING SAIDSECTIONS TO EFFECT WAVE SIGNAL TRANSMISSION BETWEEN SAID FIRST ANDSECOND LAUNCHING SECTIONS WITH SAID SECTIONS IN RELATIVE MOTION.